This mode also works without an internet connection, allowing wireless devices to network among themselves. If you can't see the use of that, you don't have five and nine-year-olds desperate to play networked games on their iPods away from home.
With the battery-powered 506 model, they can even do it in the car.
Third comes repeater mode, that also connects to an existing Wi-Fi network and extends its range, acting as a miniature satellite for the main router. We'd have less use for this trick than the others, but it is handy for evening out wireless signals in some buildings, or ensuring that the router in your home office provides ample service to guests around the barbecue.
Finally, there's a USB port and a free phone and tablet app that let your mobile devices access files on a USB stick plugged into the D-Link, and even upload pictures from your camera roll to the data key. Text files, audio and videos can all be accessed and played back. And the USB port also doubles as a phone charger.
The devices have their limitations and quirks. For instance, they can't remember previous settings, so you need to set them up again each time you return to a regular hotel, and it's important to update them to the latest firmware as earlier versions could be a little buggy. Some helpful Amazon reviewers have detailed how they get best value from these mini-routers and the manufacturer has posted a set-up guide on YouTube that will demystify them for those who haven't tinkered with routers and repeaters before. Search the title, "Setting up a D-Link DIR-505".
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